JP2005147550A - Heat pump with adsorption type cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump allowing further improvement of a COP (coefficient of performance). <P>SOLUTION: In this heat pump, a main body has a booster 10 boosting a refrigerant, a condenser 11 condensing the refrigerant boosted by the booster by heat exchange with a heated fluid such as outside air, and an evaporator evaporating the refrigerant condensed in the condenser by heat exchange with a cooled fluid such as indoor air. An adsorption type cooling device A further cooling the refrigerant condensed in the condenser 11 by an adsorbate with heat of the refrigerant boosted by the booster 10 as a regenerative heat source of the adsorbing material is attached. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat pump including an adsorption cooling device, and more particularly to a heat pump that can effectively use the heat of a refrigerant by the adsorption cooling device to further improve COP.

  As is well known, a heat pump is a device that cools and heats by utilizing the property that it takes away ambient heat when the liquid is vaporized, and conversely releases heat when the gas is condensed and liquefied. In the heat pump, an electric booster is generally used for boosting the refrigerant. However, the performance of the heat pump is based on a coefficient of performance (COP), that is, energy required for heat transfer (power energy of the booster). A heat pump with a higher COP is required from the viewpoint of energy saving, expressed in terms of the amount of heat transferred. The simplest way to increase COP is to lower the temperature of the refrigerant with a condenser.

  The cooling method of the condenser is roughly classified into a dry type and a wet type. The wet type has a large cooling effect and can cool the refrigerant to a temperature about 5 ° C. higher than the outside air temperature (for example, 35 ° C.), that is, about 40 ° C., and the effect is excellent. There are also other problems such as maintenance costs such as scaling prevention, including cooling tower management. On the other hand, the dry method requires no maintenance and is simple, but has a problem that it can be cooled only to a temperature about 15 ° C. higher than the outside air temperature (for example, 35 ° C.), that is, about 50 ° C. In the vicinity of rivers, heat pumps using river water as a low-temperature heat source have been proposed, but it cannot be said that there are many environments that can be adapted.

As a heat pump intended to increase COP, the air supplied to the condenser of the heat pump is cooled by moving the desiccant cooling air conditioner using the heat of the refrigerant boosted by the booster, and the indoor Heat pumps designed to dehumidify air have been proposed. In such a heat pump, from the viewpoint of improving COP, the idea of using the heat of the pressurized refrigerant is epoch-making. However, the air is heated via the heat exchanger with the increased pressure refrigerant, and the adsorbent of the desiccant rotor is regenerated with the heated air, so the regeneration temperature is lowered, and the dehumidifying capacity of the adsorbent cannot be sufficiently obtained. As a result, the problem of increasing the desiccant rotor is foreseen.
Japanese Patent Laid-Open No. 2001-91080

  As described above, heat pumps equipped with wet condensers are complicated to maintain such as scaling prevention, and heat pumps equipped with simple dry condensers have a small cooling effect and are equipped with a desiccant cooling air conditioner. Each heat pump has problems such as an increase in the size of the apparatus, and none of the heat pumps can be said to be excellent heat pumps. An object of the present invention is to provide a heat pump having a new structure capable of further improving COP.

   The present invention combines an adsorption type cooling device with a heat pump comprising a booster, a condenser and an evaporator, and uses the heat of the refrigerant itself that has become high temperature in the compressor to regenerate the adsorbent of the adsorption type cooling device. The refrigerant supplied to the evaporator is directly cooled by the adsorbate of the adsorption cooling device so as to be lower than the condensation temperature, thereby improving the COP of the heat pump.

  That is, the gist of the present invention is that a booster that boosts the refrigerant, a condenser that condenses the refrigerant boosted by the booster by heat exchange with the fluid to be heated, and the refrigerant condensed by the condenser is cooled. A heat pump having an evaporator for evaporating by heat exchange with a fluid, wherein the heat of the refrigerant boosted by the booster is used as a regeneration heat source for the adsorbent, and the refrigerant condensed by the condenser is used as an adsorbate In the heat pump, an adsorption type cooling device for further cooling is attached.

  According to the heat pump of the present invention, the low-temperature refrigerant further cooled by the evaporator of the adsorption cooling device is made to enter the evaporator on the main body side, and the cooling efficiency with respect to the fluid to be cooled in the evaporator is high, Since the amount of refrigerant to be circulated can be reduced, the load applied to the booster can be reduced and the COP can be further improved.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart showing the concept of the heat pump according to the present invention. FIG. 2 is a flowchart showing a configuration example of the heat pump according to the present invention. 3 and 4 are flowcharts showing the refrigerant flow and adsorbate flow during operation in the heat pump of the present invention.

  The heat pump of the present invention is a combination of a basic heat pump structure including a booster, a condenser and an evaporator with an adsorption cooling device (adsorption heat pump). The basic structure of the main body of the heat pump of the present invention is the same as that of the conventional one. As shown in FIG. 1, the booster (10) for boosting the refrigerant and the heat of condensation of the refrigerant boosted by the booster. The condenser (11) that heats the fluid to be heated by, that is, condenses the refrigerant pressurized by the booster by heat exchange with the fluid to be heated such as outside air, and the latent heat of vaporization of the refrigerant condensed by the condenser It mainly comprises an evaporator (13) that cools the fluid to be cooled, that is, evaporates the refrigerant condensed in the condenser by heat exchange with the fluid to be cooled such as room air. Reference numeral (12) in the figure denotes a pressure reducing valve (expansion valve) provided on the upstream side of the evaporator (13). Reference numerals (31), (32), (33), (34) and (35) Indicates refrigerant flow paths.

  As shown in FIG. 1, the feature of the present invention is that the heat of the refrigerant boosted by the booster (10) is used as a regeneration heat source for the adsorbent, and the refrigerant condensed by the condenser (11) is further cooled by the adsorbate. An adsorption cooling device (A) is attached. The adsorptive cooling device (A) includes an adsorber (40) that adsorbs and desorbs adsorbate, a condenser (42) that condenses and liquefies adsorbate vapor desorbed by the adsorber, and is liquefied by the condenser. It mainly comprises an evaporator (43) that evaporates the adsorbate and cools an object to be cooled (refrigerant supplied to the evaporator (13)) with its latent heat of vaporization. And in the heat pump of this invention, said adsorption device (40) of adsorption type cooling device (A) is arrange | positioned between a pressure | voltage riser (10) and a condenser (11), and pressure | voltage riser (10) The adsorbent can be regenerated by the refrigerant whose pressure has been increased by the above, and the evaporator (43) is disposed between the condenser (11) and the evaporator (13) to supply the evaporator (13). The refrigerant to be cooled can be further cooled.

  In the present invention, chlorofluorocarbons (CFC-11, CFC-12, CFC-113, CFC-114, CFC-115) are used as the refrigerant circulating through the heat pump body and the refrigerant circulating through the adsorption cooling device (A). , Hydrochlorofluorocarbon (HCFC-22, HCFC-123, HCFC-124, HCFC-141b, HCFC-142b, HCFC-225ca, HCFC-225cb), hydrofluorocarbon (HFC-23, HFC-32, HFC-125, HFC) -134a, HFC-143a, HFC-152a, HFC-227ea, HFC-236fa, HFC-245ca), fluorocarbon (FC-14, FC-116, FC-218, FC-C318), methyl bromide, ammonia, dioxide carbon Water and the like. Also. Examples of the adsorbate of the adsorption cooling device (A) include water, ethanol, and acetone.

  Hereinafter, a more detailed configuration of the heat pump of the present invention will be described with reference to FIGS. In the heat pump of the present invention, as shown in FIG. 2, a three-way valve (21) is connected to the refrigerant flow path (31) on the downstream side of the booster (10), and the refrigerant pressurized by the booster (10) is It is adapted to be taken into the adsorption cooling device (A) via the three-way valve (21). In the adsorption cooling device (A), at least two adsorbers (40) are provided, and the pressurized refrigerant passes through the refrigerant flow paths (61) and (62) on the downstream side of the three-way valve (21). For example, it flows to two adsorbers (40a) and (40b), and in the adsorbers (40a) and (40b), the adsorbent is regenerated by heating with a refrigerant.

  The refrigerant outlet of the adsorber (40a) is connected to the refrigerant flow path (63) reaching the three-way valve (22), and the refrigerant outlet of the adsorber (40b) is connected to the refrigerant flow reaching the three-way valve (22). The path (64) is connected. Therefore, the refrigerant used as the regeneration heat source of the adsorbent in the adsorbers (40a) and (40b) passes through the refrigerant flow paths (63) and (64) and the refrigerant flow path ( 32) through the condenser (11).

  In the condenser (11), the refrigerant is cooled by heat exchange with a heated fluid such as outside air. The evaporator (43) of the adsorption cooling device (A) is disposed on the downstream side of the condenser (11) via the refrigerant flow path (33), and the refrigerant cooled by the condenser (11) The refrigerant flows into the evaporator (43) of the adsorption cooling device (A) through the refrigerant flow path (33) and is further cooled by the latent heat of vaporization of the adsorbate that evaporates in the evaporator (43).

  On the downstream side of the evaporator (43) of the adsorption cooling device (A), the evaporator (13) is arranged through the refrigerant channel (34), the pressure reducing valve (12) and the refrigerant channel (35) in this order. The refrigerant cooled by the evaporator (43) passes through the refrigerant flow path (34), is decompressed by the pressure reducing valve (12), and is supplied to the evaporator (13) through the refrigerant flow path (35). Has been made. In the evaporator (13), a fluid to be cooled such as room air is cooled by the latent heat of vaporization of the refrigerant. A refrigerant flow path (36) leading to the booster (10) is connected to the downstream side of the evaporator (13), and the refrigerant evaporated by the evaporator (13) passes through the refrigerant flow path (36). , And return to the booster (10).

  That is, in the heat pump of the present invention, the booster (10), the adsorber (40) of the adsorption cooling device (A), the condenser (11), the evaporator (43) of the adsorption cooling device (A), the reduced pressure A series of cycles in which the refrigerant circulates through the valve (12) and the evaporator (13) is repeated. In the conventional heat pump, since the refrigerant is only cooled by the condenser, in the heat pump of the present invention, the refrigerant is further cooled by the evaporator (43) of the adsorption cooling device (A). 10) can be reduced, and COP can be further improved.

  Next, the structure of the adsorption cooling device (A), the flow of the heating / cooling refrigerant in the adsorption cooling device, and the flow of the adsorbate for cooling the refrigerant in the evaporator (43) will be described. In the adsorption cooling device (A), as described above, the refrigerant on the heat pump main body side is used for regeneration of the adsorbent in the adsorbers (40a) and (40b), but as a refrigerant for cooling the adsorbate. Also, the refrigerant on the heat pump main body side can be used.

  Specifically, in the adsorption cooling device (A), a cooler (45) is disposed on the downstream side of the pump (44), and the refrigerant on the heat pump main body side is transferred from the pump (44) to the cooler (45). And cooled by heat exchange with a heated fluid such as outside air in a cooler (45). A refrigerant flow path (68) leading to the condenser (42) of the adsorption cooling device (A) is connected to the downstream side of the cooler (45), and one of the refrigerants cooled by the cooler (45) is connected. Part flows through the refrigerant flow path (68) to the condenser (42). In the condenser (42), the adsorbate is cooled and condensed by heat exchange with the refrigerant. And the refrigerant flow path (69) leading to the pump (44) is connected to the downstream side of the condenser (42), and the refrigerant whose temperature has been raised by the condenser (42) passes through the refrigerant flow path (69). Thus, the pump (44) is returned again.

  In addition, a refrigerant flow path (67) reaching the three-way valve (52) is connected to the downstream side of the cooler (45), and the adsorber (40a) is connected to the downstream side of the three-way valve (52). The refrigerant flow path (80) leading to the inlet of the adsorber and the refrigerant flow path (81) leading to the inlet of the adsorber (40b) are connected, and a pump (44) is connected to the outlet side of the adsorber (40a). The refrigerant flow path (65) leading to the upstream three-way valve (51) is connected, and the refrigerant flow path (66) leading to the three-way valve (51) is connected to the outlet side of the adsorber (40b). The

  That is, another part of the refrigerant cooled by the cooler (45) flows from the refrigerant flow path (67) to the three-way valve (52), from the three-way valve (52) to the refrigerant flow path (80), and the adsorber (40a). ), Circulates again to the cooler (45) via the refrigerant flow path (65) and the three-way valve (51), or from the three-way valve (52) to the refrigerant flow path (81), the adsorber (40b), the refrigerant It circulates again to the cooler (45) through the flow path (66) and the three-way valve (51). In that case, the refrigerant flows in one of the two paths by switching the three-way valve (52), and the refrigerant does not flow in the other path while the refrigerant flows in one path.

  Subsequently, the refrigerant flow (solid arrow) and the adsorbate flow (broken arrow) during operation will be described more specifically with reference to FIGS. 3 and 4. As shown in FIG. 3, the refrigerant flowing in from the main body flow path flows from the three-way valve (21) to the refrigerant flow path (61), and partly passes from the refrigerant flow path (63) through the adsorber (40a). (22) and return to the refrigerant flow path (32) on the main body side. On the other hand, part of the refrigerant that has flowed through the cooler (45) of the adsorption cooling device (A) flows from the three-way valve (52) through the refrigerant flow path (81) to the adsorber (40b). Part of the refrigerant that has passed through 40b) flows to the three-way valve (51) on the upstream side of the pump (44) via the refrigerant flow path (66).

  At this time, the adsorber (40a) is in the desorption process, and the adsorbate adsorbed on the adsorbent of the adsorber (40a) is in the form of vapor in the adsorbate flow path (74), the three-way valve (54) and the adsorbent. It passes through the quality channel (76), flows to the condenser (42), and is cooled and condensed by the condenser. At the same time, the other adsorber (40b) is in the adsorption process, and the adsorbate vaporized in the evaporator (43) is transferred from the evaporator (43) to the adsorbate flow path (71), the three-way valve (53), and the adsorbent. It passes through the mass flow path (73), flows to the adsorber (40b), and is adsorbed by the adsorbent of the adsorber (40b). The adsorbate condensed in the condenser (42) is supplied again to the evaporator (43) through the adsorbate flow path (70) in a liquid state.

  In the adsorption cooling device (A), the adsorber (40a) and the adsorber (40b) are operated while being switched at certain intervals. In the above case, the adsorber (40a) was the regeneration process and the adsorber (40b) was the adsorption process, but the refrigerant flow (solid arrow) and adsorbate flow (broken arrow) after switching are shown in FIG. As shown in That is, when the operation of the adsorber (40a) and the adsorber (40b) is switched, as shown in FIG. 4, the refrigerant passes from the three-way valve (21) to the adsorber (40b) via the refrigerant flow path (62). The refrigerant that has flowed and passed through the adsorber (40b) flows through the refrigerant flow path (64) to the three-way valve (22) and returns to the refrigerant flow path (32) on the main body side. On the other hand, a part of the refrigerant that has flowed through the cooler (45) of the adsorption cooling device (A) flows from the three-way valve (52) through the refrigerant flow path (80) to the adsorber (40a), and the adsorber (40a) Part of the refrigerant that has passed through 40a) flows through the refrigerant flow path (65) to the three-way valve (51) on the upstream side of the pump (44).

  At this time, the adsorber (40b) is in the desorption process, and the adsorbate adsorbed by the adsorbent of the adsorber (40b) is in the state of vapor in the adsorbate flow path (75), the three-way valve (54), It passes through the quality channel (76), flows to the condenser (42), and is cooled and condensed by the condenser. At the same time, one adsorber (40a) is in the adsorption process, and the adsorbate vaporized in the evaporator (43) is adsorbed from the evaporator (43) to the adsorbate flow path (71), the three-way valve (53), and the adsorbent. It passes through the mass channel (72), flows to the adsorber (40a), and is adsorbed by the adsorbent of the adsorber (40a). The adsorbate condensed in the condenser (42) is supplied again to the evaporator (43) through the adsorbate flow path (70) in a liquid state.

  That is, in the adsorption cooling device (A), the adsorbate is evaporated in the evaporator (43) by the adsorption operation of either the adsorber (40a) or (40b), and the adsorber (40a) or (40b). Is desorbed from the adsorber (40a) or (40b) by the desorption operation of the adsorber (40a) or (40b), flows to the condenser (42), and is cooled by the condenser (42). And it is condensed and returns to the evaporator (43). And when evaporating in an evaporator (43), the temperature of the main body side refrigerant | coolant which flows through a refrigerant | coolant flow path (34) from a refrigerant | coolant flow path (33) is further reduced with the latent heat of vaporization.

  Next, with reference to FIG. 4, the temperature of the refrigerant in the entire apparatus, and the conditions of the adsorbent suitable for driving the adsorption cooling apparatus (A) will be described. The refrigerant is compressed by the compressor (10) and the temperature rises to about 90 degrees. The refrigerant enters the adsorber (40b) through the three-way valve (21) and the refrigerant flow path (62) and heats the adsorbent, but the temperature of the refrigerant when it flows out of the adsorber (40b) is the flow rate. However, according to the inventors' research, the temperature is 60 to 70 ° C. The temperature of the regenerated adsorbent is 60 to 70 ° C.

  The refrigerant after heating the adsorbent passes through the refrigerant flow path (64) and the three-way valve (22), flows to the condenser (11), is cooled by the condenser, for example, by the atmosphere, and is discharged from the condenser (11). In the vicinity, it is cooled to 43 ° C. In general, the air cooling system cools only to a temperature about 10 ° C. higher than the outside air temperature. Therefore, assuming that the outside air temperature in summer when the cooling is required is 33 ° C., the temperature is 43 ° C. near the outlet.

  The refrigerant is further cooled by the evaporator (43) of the adsorption cooling device (A) through the refrigerant flow path (33). Depending on the performance of the heat exchanger in the evaporator (43), when cooled to a temperature about 15 ° C. lower than the inlet temperature of the evaporator (43), the outlet temperature of the evaporator (43) becomes 28 ° C. . In the case of a conventional heat pump (compression refrigeration machine) that does not have an adsorption cooling device (A), the heat pump of the present invention that has an adsorption cooling device (A) has a 43 ° C refrigerant in the evaporator. Since the refrigerant of 28 ° C., which is 15 ° C. lower, enters the evaporator (13), the cooling efficiency of the fluid to be cooled such as room air is high, and the amount of refrigerant to be circulated can be reduced, so that the power of the compressor (10) can be reduced. , COP can be greatly improved.

  Further, the temperature of the refrigerant in the adsorption cooling device (A) will be described. When the refrigerant is cooled to 38 ° C. by the cooler (45), a part of the refrigerant flows into the condenser (42), and the adsorbate is It rises to about 43 ° C. due to the heat of condensation generated during condensation. Then, the high-temperature refrigerant returns to the cooler (45) through the refrigerant flow path (69) and the pump (44), and is cooled again to 38 ° C. Further, another part of the refrigerant cooled by the cooler (45) passes through the three-way valve (52) and the refrigerant flow path (80) and enters the adsorber (40a) to cool the adsorbent. At this time, the temperature rises due to the heat of adsorption when the adsorbent adsorbs the adsorbate, but rises to about 43 ° C. at the outlet of the adsorber (40a) and returns to the cooler (45). In addition, the above temperature conditions are the temperature which assumed the combination of a certain temperature condition and a heat exchanger, and this invention is not limited only to this condition.

  The adsorption characteristics required for the adsorbent based on the refrigerant temperature will be described as follows. In the adsorption step, for example, the adsorbent of the adsorber (40a) is cooled to 38 to 43 ° C. and adsorbs adsorbate such as water vapor of about 28 ° C. supplied from the evaporator (43). The relative humidity φ2 of the adsorbent in the adsorption step is obtained from the following equation (1), and the adsorbent temperature (T2) is 43 ° C. and the sump temperature (water temperature in the evaporator (43)) (T0). When it is 28 ° C., the relative humidity φ2 is 43.7%. Therefore, as the adsorbent used in the adsorption-type cooling device (A), an adsorbent that sufficiently adsorbs at a place where the relative water vapor pressure is 43.7% in the water vapor adsorption isotherm at 43 ° C. is usually used. Preferably, an adsorbent that sufficiently adsorbs at a relative water vapor pressure of 50.0% in a water vapor adsorption isotherm at 40 ° C. is used, more preferably an adsorbent that sufficiently adsorbs at 45.0%, and even more preferably 43% is sufficient. Adsorbents that adsorb are used.

  In the desorption process, for example, the adsorbent of the adsorber (40b) is heated to 60 to 70 ° C, and the adsorbate is condensed at 38 to 43 ° C in the condenser (42). The relative humidity φ1 in the desorption process can also be obtained from the following equation 2 similarly to the above φ2. In the desorption process, when the adsorbent is heated to 60 ° C. and the temperature of the condenser (42) is 43 ° C., the relative water vapor pressure is 43.4%. Therefore, as the adsorbent, an adsorbent that does not adsorb so much at a relative water vapor pressure of 43.4% is usually used. Preferably, an adsorbent that does not adsorb much at a relative vapor pressure of 28.0% is used in a 60 ° C. water vapor desorption isotherm, more preferably an adsorbent that does not adsorb so much at 35.0%, even more preferably less at 43%. Adsorbents that do not adsorb are used.

  The difference ΔQ between the adsorption amount Q2 adsorbed at the relative humidity φ2 and the adsorption amount Q1 adsorbed at the relative humidity φ1 is preferably as large as possible. The difference ΔQ in the amount of adsorption is preferably 0.10 g / g or more, more preferably 0.15 g / g or more, and still more preferably 0.20 g / g or more. Although it is desirable that the difference ΔQ in the amount of adsorption is large, if ΔQ is large, the volume of pores to be made into the adsorbent increases, and the bulk density decreases. Therefore, the difference ΔQ in adsorption amount is preferably 1.00 g / g or less.

  In the present invention, various adsorbents can be used as long as they exhibit the above characteristics. As the adsorbent, for example, silica gel, activated carbon, mesoporous silica, zeolite, activated alumina and the like can be used, and among these, mesoporous silica and activated carbon are preferable. For some adsorbents, the following table shows the results of confirming each adsorption amount at the relative humidity φ2 and relative humidity φ1 and the difference ΔQ between the adsorption amounts. In the table, samples 1 to 5 are preferable adsorbents, and samples 6 and 7 are inappropriate adsorbents. In addition, the adsorbent “SBA-1” in the table is typical mesoporous silica. “Kinol” is a trade name of Gunei Chemical Co., Ltd., and is an adsorbent made of activated carbon fiber made from phenol resin. Nitric acid treatment refers to the surface of activated carbon fiber oxidized with nitric acid.

It is a flowchart which shows the concept of the heat pump which concerns on this invention. It is a flowchart which shows the structural example of the heat pump which concerns on this invention. It is a flowchart which shows the flow of the refrigerant | coolant in operation | movement in the heat pump of this invention, and the flow of adsorbate. It is a flowchart which shows the flow of the refrigerant | coolant in operation | movement in the heat pump of this invention, and the flow of adsorbate.

Explanation of symbols

10: Booster 11: Condenser 12: Pressure reducing valve (expansion valve)
13: Evaporator 40: Adsorber 42: Condenser 43: Evaporator 44: Pump 45: Cooler

Claims (2)

  A booster that boosts the refrigerant, a condenser that condenses the refrigerant boosted by the booster by heat exchange with the fluid to be heated, and evaporates the refrigerant condensed by the condenser by heat exchange with the fluid to be cooled A heat pump having a main body with an evaporator, wherein the heat of the refrigerant boosted by the booster is used as a regeneration heat source for the adsorbent, and the refrigerant condensed by the condenser is further cooled by adsorbate Is a heat pump.   The adsorption cooling device includes an adsorber that adsorbs and desorbs the adsorbate, a condenser that liquefies the adsorbate vapor desorbed by the adsorber, and an evaporator that evaporates the adsorbate liquefied by the condenser. And, the adsorber of the adsorption type cooling device is disposed between the booster and the condenser of the main body, so that the adsorbent can be regenerated by the refrigerant boosted by the booster of the main body, and the adsorption 2. The heat pump according to claim 1, wherein the evaporator of the type cooling device is arranged between the condenser and the evaporator of the main body so that the refrigerant supplied to the evaporator of the main body can be cooled.

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